How to interpret normal distribution mean and standard deviation.

Which shows the correct substitution of the values a,b and c from the equation 1=-2x+3x^2+1

Complete the solution of the equation. find the value of y when x equals -5. -4x - 8y = -52

Suppose a laboratory has a 30 g sample of polonium-210. the half-life of polonium-210 is about 138 days how many half-lives of polonium-210 occur in 1104 days? how much polonium is in the sample 1104 days later? 9; 0.06 g 8; 0.12 g 8; 2,070 g