We wish to study the competition of grass species: in particular, big bluestem (from the tall grass prairie) versus quack grass (a weed). We set up an experimental garden with 24 plots. These plots were randomly allocated to the six treatments: nitrogen level 1 (200 mg N/kg soil) and no irrigation; nitrogen level 1 and 1cm/week irrigation; nitrogen level 2 (400 mg N/kg soil) and no irrigation; nitrogen level 3 (600 mg N/kg soil) no irrigation nitrogen level 4 (800 mg N/kg soil) and no irrigation; and nitrogen level 4 and 1 cm/week irrigation. Big bluestem was seeded in these plots and allowed to establish itself. After one year, we added a measured amount of quack grass seed to each plot. After another year, we harvest the grass and measure the fraction of living material in each plot that is big bluestem. We wish to determine the effects (if any) of nitrogen and/or irrigation on the ability of quack grass to invade big bluestem. (Based on Wedin 1990.) N level 1 1 2 3 4 4
Irrigation N Y N N N Y
97 83 85 64 52 48
96 87 84 72 56 58
92 78 78 63 44 49
95 81 79 74 50 53

Required:
a. Do the data need a transformation? If so, which transformation?
b. Provide an Analysis of Variance for these data. Are all the treatments equivalent?
c. Are there significant quadratic effects of nitrogen under nonirrigated conditions?
d. Is there a significant effect of irrigation?
e. Under which conditions is big bluestem best able to prevent the invasion by quack grass? Is the response at this set of conditions significantly different from the other conditions?

Assume that to_the_power_of is a function that expects two int parameters and returns the value of the first parameter raised to the power of the second parameter. write a statement that calls to_the_power_of to compute the value of cube_side raised to the power of 3 and that associates this value with cube_volume.

Johnson enterprises uses a computer to handle its sales invoices. lately, business has been so good that it takes an extra 3 hours per night, plus every third saturday, to keep up with the volume of sales invoices. management is considering updating its computer with a faster model that would eliminate all of the overtime processing.

Write a program that reads in a series of lines of input character by character (using the library function the first line of the input contains an integer which specifies the number of remaining lines of input, each of which contains a floating point number. the integer value on the first line can be read with (the library function) but all of the following lines can only be read with each line, after the first, contains a single floating point value, with up to four digits before the decimal point, and up to four digits following the decimal point, but there is not necessarily a decimal point in each number; i.e., it may appear to be an integer, but the digits should be read by your program, and the number should be converted to a corresponding floating point number. for instance, suppose the following input: 5 3.1255 20.25 0.875 1921.50 31 the required output is: − each of the input floating point values, printed on a separate line with four digits of precision, using printf(); − on the last line of the output, the string “total: ” followed by the sum of the input values, printed with printf() to 4 digits of precision. for example, the total of the sample input given above is 1976.7505, so the required output for this input would be: 3.1255 20.2500 0.8750 1921.5000 31.0000 total: 1976.7505 do not concern yourself with small differences in the total due to rounding, as the grader will not deduct points for this. constraints: − you are not allowed to use arrays on this portion of the lab assignment. − there is no maximum number of lines allowable. it all depends upon the first value of input. since you aren’t saving anything, it doesn’t matter. − you can assume that input will not contain more than 4 digits before or after the decimal point. you do not need to error check for this condition. -you must use getchar() to read in the floating point values one character at a time (i.e. do not use -you must declare and use your floating point values as a double to minimize rounding errors. -only use printf() to output the floating point numbers and the total (do not use − be sure your directions to the user are clear so they are sure to enter the input data correctly.