Help please i need this in less that 3 minutes. i just need the formula or what to do

Which expression calculates the speed in meters per second of an object that travels a distance of 100 m every 20 seconds

Yoku is putting on sunscreen. he uses 2\text{ ml}2 ml to cover 50\text{ cm}^250 cm 2 of his skin. he wants to know how many milliliters of sunscreen (c)(c) he needs to cover 325\text{ cm}^2325 cm 2 of his skin. how many milliliters of sunscreen does yoku need to cover 325 \text{ cm}^2325 cm 2 of his skin?

Solve the inequaliy: (x^2+2)(x−2)^2(6−2x)> 0