F(x)=\begin{cases}-(x-2)^2-3 & \text{ for }\hspace{10px} x< 4 \\ -5 & \text{ for }\hspace{10px} x=4 \\ \frac{1}{2}x-10 & \text{ for }\hspace{10px} x> 4\end{cases} f(x)= ⎩ ⎪ ⎨ ⎪ ⎧ −(x−2) 2 −3 −5 2 1 x−10 for x< 4 for x=4 for x> 4

The number of nails of a given length is normally distributed with a mean length of 5.00 in, and a standard deviation of 0.03 in. find the number of nails in a bag of 120 that are less than 4.94 in. long.

Write the point-slope form of the line passing through (2, -12) and parallel to y=3x.

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?