Aprojectile is thrown upward so that its distance above the ground after t seconds is h = - 16t2 + 440t.. after how many seconds does it reach its maximum height?

Which expressions are equivalent to k/2 choose 2 answers: a k-2 b 2/k c 1/2k d k/2 e k+k

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

Write a polynomial function f of least degree that has rational coefficients, a leading coefficient of 1, and the given zeros. 3, 4+2i, 1+(sqrt)7 the answer is supposed to be: f(x)=x(^5)-13x(^4)+60x(^3)-82x(^2)- 144x+360 what am i doing wrong?