Carbon-14 is a radioactive isotope that decays exponentially at a rate of 0.0124 percent a year. How many years will it take for carbon-14 to decay to 10 percent of its original amount? The equation for exponential decay is At = A0e-rt.

Draw a diagram that shows 0.27+0.23 = 1/2

B) y and z are whole numbers. y < 70 Z<60 Work out the largest possible value of y + z

Simplify (1/5 - 1/10) •3^2-4/5

What does the "quadratic portion" of a quadratic equation mean?

For each 24 mm of coloured fabric Gordon uses to make his curtains, he also uses 1.2 cm of white fabric. Express the amount of white fabric to coloured fabric as a ratio in its simplest form.

13[42 - (2+4) second power]

Which is bigger 5/8 or 0.58

What is nine more than a number divided by - 4 when it is less than or equal to - 2

If x2 - y2 = 12 and x - y = 4, what is the value of x2 + 2xy + y? F. 3 G. 8 H. 9 J. 12 K. 16

Data collected in a survey shows that 60 percent of the buyers are interested in buying a brand of mobile phone and if the total number of buyers are 400 then how many buyers are not interested and also find the central angle of the sector of the