Answer:
5 weeks.
Step-by-step explanation:
John can create 3 apps in 6 weeks, so his rate is (3 apps / 6 weeks) = 1/2 app per week.
Ben can do same job i.e. 3 apps in 2 weeks, so his rate is (3 apps / 2 weeks) = 3/2 app per week.
Their combined rate is (1/2 + 3/2) = 4/2 = 2 apps per week.
It means they together can create 2 apps in 1 week.
So, they together can create 10 apps in 5 weeks.
5.498 - C
Length of an arc = tetha/360 × 2 × pi × r
Converting 7pi/4 to tetha
(7 × 180) / 4 = 315°, since pi = 180°
Plugging values to the formula:
315/360 × 2 × 3.142 × 1 = 5.498units
b