Help with circles plz ASAP

The indicated measure is:55⁰

To prove that thry are the circles diameters you can do it by two methods.One is calculating all the angles and the sum of all angles of it equals 360⁰.The one that is the opposite point of 55⁰ is 55⁰ so we need to find the other by : 180⁰-55⁰=125⁰. So 125⁰×2+55⁰×2=360⁰.

The second method is by knowing the rule that applies to diameters of a circle and that says that : a diameter is formed when a line goes from a point to the circle and passes the main point and then finishes to another point in the cirlcle.

a = 11 : 4

b = 38

c = 1 for every 6

answer: - (a)

(b) 88 seats

step-by-step explanation:

given: in an auditorium, there are 22 seats in the first row and 28 seats in the second row.

thus first term=

second term=

the number of seats in a row continues to increase by 6 with each additional row.

⇒d= 6

a) given formula :

b)   let the number of seats (n) = 12

substitute n=12 in the explicit rule formed in (a)

∴there are 88 seats in 12 rows.