What is 62,394 to the nearest ten

For f(x)=2x+1 and g(x)= x^2 -7, find (f•g)(x)

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Acircle has a radius of 5/6 units and is centered at (3.6, 7.8) write the equation of this circle