All human blooid is one of the four types : o , a, b or ab. the distributions of the types varies a bit with race. if you choose an african american person at random , here is a table of the approcimate probabilities of that person having each of the different blood types.

blood types : o a b ab
0.5 ? 0.2 0.05

using the table of probabilities above , the probability that the person chosen has blood type a is :
0.05
0.25
0.27
0.40
0.65

i'm having a bit of trouble with probability may someone walk me through it , i'm willing to learn!

With these 5 geometry questions! pls 1.)quadrilateral abcd is inscribed in this circle. what is the measure of ∠a ? enter your answer in the box.°2.)quadrilateral abcd is inscribed in a circle. what is the measure of angle a? enter your answer in the box. m∠a= 3.)quadrilateral abcd is inscribed in this circle. what is the measure of angle b? enter your answer in the box. m∠b= °4.)quadrilateral abcd is inscribed in this circle. what is the measure of angle a? enter your answer in the box.°5.) quadrilateral abcd is inscribed in this circle. what is the measure of angle c? enter your answer in the box.°