I will give brainliest

Step-by-step explanation:

make a right triangle to find the lenght of a side  which is also the hypotenuse of the triangle

c² = a² + b²

c² = 7² + 5²

c²  = 49 + 25

c²  =  = 74

Since the area of a square is s² and c = s

a = c²

a = 74 units²

1/800 is the right answer

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