If 12-6r=r+8-3r what is the value of r + 4

Which expression is equivalent to −16y+13 ? −16(−y+13) 16(−y+2) −16(y+2) 16(−y+13)

Describe in detail how you would construct a 95% confidence interval for a set of 30 data points whose mean is 20 and population standard deviation is 3. be sure to show that you know the formula and how to plug into it. also, clearly state the margin of error.

He mass of a single atom of carbon can be found by dividing the atomic mass (12.01 g) by 6.022 x 10^23. which is the mass of a single carbon atom, correctly written in scientific notation with the correct number of significant figures?