Unformatted text preview: (b) How many years after ﬁshing stopped was it until the number of ﬁsh in the lake reach 3800? 3. Adult movie tickets cost 6. Child tickets cost 3. If 700 people go to a movie and the total ticket sales are 3300, how many children and how many adults are there? 4. The mass, m ( t ), of a radio-active substance decreases as it decays and satisﬁes the equation m ( t ) =-. 5 m ( t ). Here time is measured in years and mass in grams. If there was initially 100 grams of this radio-active substance, how much is there after 5 years? What is the half life? 5. The height of water in a harbor varies like a sine wave with a period of 11 hours. The maximum height is 30 feet and the minimum height is 20 feet. T is the time measured in hours. The height at time T=0 is 25 feet. Write down a function which gives the height of the water at time T....
View Full Document
- Fall '07
- Half-Life, Sine wave, blue book