Aman's speed with the current is 15km/hr and the speed of the current is 2.5km/hr. the man's speed against the current is

10 km/h  

Step-by-step explanation:

Let s = man's speed and c = speed of current

    s + c = 15

         c = 2.5     Insert value of c

s + 2.5 = 15        Subtract 2.5 from each side

        s = 12.5 km/h

Speed against current

= 12.5 – 2.5

= 10 km/h

answer: option a.

step-by-step explanation:

you know that the quadrilateral opqr ( a four sided figure) is inscribed in circle. this means that all its vertices are on the circle.

then, by definition, the opposite angles of the quadrilateral are supplementary, this means that the sum of their measures is 180 degrees.

you can observe in the figure that the angles ∠opq   and the angle ∠orq   are opposite, therefore:

then, can be used to d to calculate the measure of ∠opq