A student is implementing an investigation of physical properties using samples of metals, nonmetals, and metalloids. She used a battery, wires, and a bulb to test if each of the samples will complete the circuit causing the bulb to light. Next, she shined a bright light on each of the samples. Which physical properties is the student investigating? hardness and luster

streak and conductivity

streak and hardness

luster and conductivity

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