A trapezoidal channel has a bottom width of 6m and side slope of 1:1. The depth of flow is 1.5 m at a discharge of 15 cum/sec. The hydraulic radius and hydraulic average depth of flow respectively are

A

1.098 m, 1.25 m

B

2.239 m, 2.50 m

C

1.25 m, 1.098 m

D

2.50 m, 2.239 m