Help please, help please

Can you me find the missing length. i attached an image.

Answer asap ill give ! ’ a sample of radioactive material decays over time. the number of grams, y , of the material remaining x days after the sample is discovered is given by the equation y = 10(0.5)^x. what does the number 10 represents in the equation? a. the half-life of the radioactive material, in days b. the amount of the sample, in grams, that decays each day c. the time, in days, it will take for the samples to decay completely d. the size of the sample, in grams, at the time the material was discovered

Estimate the time en route from majors airport (area 1) to winnsboro airport (area 2). the wind is from 340° at 12 knots and the true airspeed is 136 knots. magnetic variation is 5° east.