Which of the following steps could be used as a shortcut method to multiply 12 by 50

The depth of a lake at a certain point, wich is a function of the distance of that point from shore, is 30 feet.

Use the radius you found in part i (r=26.8 cm) with the surface area formula below to find the surface area of the sphere. show your work and round your answer to the nearest tenth. the surface area of a sphere: sa = 4πr^2 self note: 3.8.4

How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way