Someone please help me

Three coins are flipped. what is the probability that there will be at least two tails?

Acompany that manufactures and sells guitars made changes in their product range. from the start they had 20 models. then they reduced the number of models to 15. as a result, the company enjoyed a 10% increase in turnover. - how much did the stock level change? in (%)

Which shows the first equation written in slope-intercept form? 1/2 (2y + 10) = 7x