I need help with this this if answered correctly I’ll give 30 more points

Compute the standard deviation of the following set of data to the nearest whole number. 10, 10, 15, 20, 25

Mahnoor randomly selects times to walk into a local restaurant and observe the type of music being played she found that the restaurant was playing country 11 times rock & roll 17 times and blues 8 times use the observed frequencies to create a probability model for the type of music the restaurant is playing the next time mahnoor walks in.

What is the product of (4x + - 5)? a) -8x^2 - 26x - 15 b) -8x^2 + 26x - 15 c) -8x^2 - 26x + 15