I NEED HELP The half-life of radium-222 is approximately 38 seconds.

Determine a so that A(t)=A0a^t describes the amount of radium-222 left after t seconds, where A0 is the amount at time t=0.

ROUND TO SIX DECIMAL PLACES.

Given: △abc, ab=15, bd=9 ad ⊥ bc , m∠c=30°. find: the perimeter of the triangle.

Acircle has a circumference of 2 pi cm. which statement about the circumference and area is true? a comparison of the area and circumference is not possible since the area cannot be determined. the numerical values of the circumference and area of the circle are equal. the numerical value of the circumference is greater than the numerical value of the area. the numerical value of the circumference is less than the numerical value of the area.

The probability that you roll a two on a six-sided die is 1 6 16 . if you roll the die 60 times, how many twos can you expect to roll