Marie's balance is initially $100 less, but she deposits $10 more per week than Oliver does. It will take her 100/10 = 10 weeks to catch up to Oliver's balance.
Oliver and Marie will have the same balance after 10 weeks.
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Oliver's balance at that time will be 300 +10×10 = 400.
Marie's balance at that time will be 200 +10×20 = 400. (the same)
The sphere has a diameter of 32 in. CORRECT: the diameter of a sphere doubles its radio, so if the radio equals 16,the diameter measures the double, in this case, 32.
The radius' lenght is one half the length of the diameter. CORRECT: , by definition, the diameter is the maximum distance between two opposite points on the surface of the sphere, and its lenght equals twice the radius because the radius is the distance between the center of the sphere and any point of the frontier of the sphere (then, one colud imagine that the distance between two opposite points in a sphere can be united by two radius, or a diameter).
The volume (V) of a sphere can be calculated as , where r is the radio. In this case, the volume of the sphere will be , which is also equal to .
, where r is the radio. In this case, the volume of the sphere will be
, which is also equal to
.