This topic contains a solution. Click here to go to the answer

Author Question: An archaeologist finds the 14C in a sample of 3.10 g of material to be decaying at 107 counts per ... (Read 48 times)

nummyann

  • Hero Member
  • *****
  • Posts: 576
An archaeologist finds the 14C in a sample of 3.10 g of material to be decaying at 107 counts per second. A modern 1.00-g sample of the same material decays at 151 counts per second. The half-life of 14C is 5730 y. How old is the sample?
 
  A) 12,200 y
  B) 8460 y
  C) 25,100 y
  D) 12,600 y

Question 2

A porch roof that slopes upward at 45 measures 3.0 m  5.0 m. It is covered with a slab of insulating material that is 2.0 cm thick.
 
  If the density of the insulation is 15 kg/m3, what is the weight of the insulation, in pounds, on the roof? (1.00 kg weighs 2.2 lb and density is mass per unit volume.)
  A) 4.5 lb
  B) 9.0 lb
  C) 20 lb
  D) 990 lb
  E) 9.9 lb



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

cuttiesgirl16

  • Sr. Member
  • ****
  • Posts: 345
Answer to Question 1

A

Answer to Question 2

E



nummyann

  • Hero Member
  • *****
  • Posts: 576
Both answers were spot on, thank you once again




 

Did you know?

HIV testing reach is still limited. An estimated 40% of people with HIV (more than 14 million) remain undiagnosed and do not know their infection status.

Did you know?

Many people have small pouches in their colons that bulge outward through weak spots. Each pouch is called a diverticulum. About 10% of Americans older than age 40 years have diverticulosis, which, when the pouches become infected or inflamed, is called diverticulitis. The main cause of diverticular disease is a low-fiber diet.

Did you know?

IgA antibodies protect body surfaces exposed to outside foreign substances. IgG antibodies are found in all body fluids. IgM antibodies are the first type of antibody made in response to an infection. IgE antibody levels are often high in people with allergies. IgD antibodies are found in tissues lining the abdomen and chest.

Did you know?

Drugs are in development that may cure asthma and hay fever once and for all. They target leukotrienes, which are known to cause tightening of the air passages in the lungs and increase mucus productions in nasal passages.

Did you know?

Women are 50% to 75% more likely than men to experience an adverse drug reaction.

For a complete list of videos, visit our video library