If sarah works at the concession stand for 2 hours, she’ll earn $ 15.50, but if she works for 4 hours, she’ll earn $ 31. find the rate of change ?

$15.50/(2 h) = $7.75/h = $31.00/(4 h)

Sarah makes $7.75 per hour.

While you might be interested in hours per dollar, the customary way to express earnings is in dollars per hour. Either is a "rate of change."

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.

perimeter of the base times height

step-by-step explanation: