The weight of an object is the product of its mass and the acceleration of gravity.
If g[e] is the acceleration of gravity on earth, and g[M] the same for Mars and g[m] the same for the moon,
then m[M]=m[e]g[M]/g[e] and m[m]=m[e]g[m]/g[e] where m[ ] denotes mass. Note that weight=mg (measured in newtons) while mass is in kilograms.
If g[M]=g[e]/3 and g[m]=g[e]/6 approximately. Then the weight of an object on Mars will be about a third of what it is on earth, while on the moon it would be about a sixth of what it is on earth.
The top one is the answer
The answer for the question is 20.25
1. sqrt(98) = 7 sqrt(2)
2. sqrt(y^6) = y^3
3. sqrt(a^7) = a^7/2
4. sqrt(12x^3y^2) = 2xy sqrt(3x)
5. sqrt(36x^2y^4) = 6xy^2
6. sqrt(48ab^3) = 4b sqrt(3ab)
7. sqrt(10a^5b^2) = a^2b sqrt(10a)
8. sqrt(20x^3y^10 = 2xy^5 sqrt(5x)
L=1.5w
P=l+w
40=2.5 w
W=16
L=1.5(16) =24
Length is 24
Width is 16