(19) Another spacecraft that uses Plutonium-238 to generate electricity is the Voyager 1 spacecraft, which launched in 1977. If Pu-238 has a half-life of 87.7 years, what percent of the nuclear fuel remains in the RTG aboard Voyager 1 today? Show your work. [Hint: Use the equation N = e^(-0.008 t)] (20) How many years will pass before 25% of the Pu-238 in Voyager 1 remains? Show your work or explain your reasoning.

Most crimes involve some evidence relating to the human body; for that reason, what related science is frequently used in forensic investigations? a)psychiatry b)physics c)botany d)biology

Which of the following statements is most likely correct about a rock belonging to the jurassic age and a rock belonging to the cambrian age? options: 1) they have identical fossils of organisms that have evolved over time. 2) both have animal fossils preserved in them due to weathering and erosion. 3) they contain different fossils because life on earth has changed through time. 4) the fossils in them were formed on the surface of earth due to exposure to sunlight.

What mistake did john needham make that caused him to conclude that spontaneous generation for microorganisms occurred? a. he re-contaminated his boiled broth solutions. b. he destroyed the vital force in the solutions. c. he did not boil his broth solutions, only warmed them. d. he failed to seal his flasks of boiled broth. e. he allowed his assistant to conduct the experiment which he did not monitor closely.