Sean is conducting an experiment with an isotope of a particular element that has a half life of 4 hours. He begins with a sample of the isotope with a mass of 92 grams. He then measures the mass of the object every hour. What is the approximate mass of the sample after 20 hours. Choices are: A: 2.875 B:2,944 C:1.4375 D:0.0313

Larry bar opened a frame shop and completed these transactions: larry started the shop by investing $41,100 cash and equipment valued at $19,100 in exchange for common stock. purchased $180 of office supplies on credit. paid $2,300 cash for the receptionist's salary. sold a custom frame service and collected $5,600 cash on the sale. completed framing services and billed the client $310. what was the balance of the cash account after these transactions were posted?

If set d is not the empty set but is a subset of set e, then which of the following is true? d ∩ e = d d ∩ e = e d ∩ e = ∅

Which equation can be used to measure the density of water in a spherical water tank? let w represent the number of water particles within the region.