You find a radioactive substance in the chemistry storage locker. You measure the mass of the substance and find that it is 5 grams. You do some research and find that this substance has a half-life of 10 seconds. How much mass of this substance was in the chemistry storage locker 1 hour before you found it? 0 10 grams O 40 grams O 120 grams O 320 grams O 640 grams O It is impossible to know the starting mass of any substance due to radioactive day.​

The a992 steel rod bc has a diameter of 50 mm and is used as a strut to support the beam. determine the maximum intensity w of the uniform distributed load that can be applied to the beam without risk of causing the strut to buckle. take f.s. = 2 against bucklin

If an astronaut takes an object to the moon the following is true (choose only one). a the mass will change but the weight will be the same. b both the mass and the weight of the object will be the same. c the weight will change but the mass will be the same. d both the mass and the weight of the object will change.

Consider a file currently consisting of 200 blocks. assume that the file control block (and the index block in the case of indexed allocation) is already in memory. calculate how many disk i/o operations are required for contiguous, linked, and indexed (single-level) allocation strategies, for each of the conditions listed below. in the contiguous-allocation case, assume that there is not room to grow at the beginning but there is room to grow at the end. also assume that the block information to be added is stored in memory.