Over the last 2.5 years, the water level in a lake has changed by -0.3 feet per year. Scientists predict that the water level will continue to go down for the next 5 years at a rate of 0.4 feet per year.

Based on this information, Andrew made several claims. Determine whether each of the claims he makes is true or false.

A
In the last 2.5 years, the water level has decreased 0.75 feet.

True False
B
The overall change of the water level after 7.5 years will be -2.75 feet.

True False
C
The change in water level each year for the next 5 years will be -0.4 feet.

True False
D
The overall change in water level for the next 5 years is equal to 5(0.4).

True False

Step-by-step explanation:

A)

"In the last 2.5 years, the water level has decreased 0.75 feet."

In the very first statement it has been stated that over the last 2.5 years, the water level in a lake has changed by -0.3 feet per year. That means in the last 2.5 years , total decrease in level is as follows

2.5 x - 0.3 = - .75 ft .

So the statement is true.

B)

"The overall change of the water level after 7.5 years will be -2.75 feet."

This statement appears to be false based on information provided

No prediction regarding rate of decrease for a period beyond 5 year  has been made so any statement with respect to a timeline of 7.5 years may turn out to be false.

C)

"The change in water level each year for the next 5 years will be -0.4 feet. "

This statement prima-facie appears to be true  because rate of decrease stated in the statement is 0.4 ft /year for next 5 years .

D )

"The overall change in water level for the next 5 years is equal to 5(0.4)"

this statement is true

as change in one year = .4

change in 5 years = 5 x .4

add all the numbers and check the ones place.

the answer is 486. as the ones place is more than 4, the estimation will be the next 10 ie, 490

what i would say the best answer is a. 40.5