Can someone plz help me on number 4

The weights of players in a basketball league are distributed normally. the distance (d) of each player's weight (w) from the mean of 86 kilograms was computed as follows: d = |w - 86| if d is greater than 7 for approximately 5% of the players, what is the approximate standard deviation of the players' weights? a. 1.75 kilograms b. 3.5 kilograms c. 4.3 kilograms d. 7 kilograms

Find the distance between (0,5) & (-4,2)

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle