Ariver is rising at a rate of 3 inches per hour. if the river rises more than 2 feet, it will exceed flood stage. how long can the river rise at this rate without exceeding flood stage?

8 hours.

Step-by-step explanation:

Given:- A river is rising at a rate of 3 inches per hour.

⇒ In one hour, the increase in the level of river= 3 inches

If the river rises more than 2 feet, it will exceed flood stage.

⇒ the level of river must be less than 2 feet

We know that, 2 feet=2×12 inches [1 foot= 12 inches]

⇒ 2 feet = 24 inches

Thus time taken to rise at the same rate without exceeding flood stage

= i.e. Time taken to reach 24 inches=

= 8 hours.

a. 12.5 kg

step-by-step explanation:

f = ma

so

m = f/a = (2500 n)/(200 m/s²) = 12.5 kg

1 n = 1 kg·m/s²