Problem:OPTIONS:
- keeps the organism warm
- lima beans
- whales
- objects that have mass
- it needs them
- most cephalopods
- barnacles
- sharks

Fact 1: Most mollusks have shells. Fact 2: Cephalopods are a class of marine mollusks. Given the two facts above, what have shells?
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A: most cephalopods

Problem:OPTIONS:
- a hurricane
- soils
- a delta
- an ocean
- soft soil
- an island
- detritus
- spring

Fact 1: Adelta is formed by deposition of sediment at the mouth of a river by water fanning out. Fact 2: Rivers provide a water supply. Given the two facts above, what is formed by deposition of sediment at the mouth of a water supply fanning out?
****
A: a delta

Problem:OPTIONS:
- drought
- Pollution
- storms
- Temperature
- heat
- contamination
- acid rain
- climate

Fact 1: Gases from burning coal and oil dissolving in water in the atmosphere causes acid rain. Fact 2: Coal-fired plants Are power stations which burn coal to generate electricity. Given the two facts above, power stations which generate electricity produce gases in the atmosphere cause what?
****
A: acid rain

Problem:OPTIONS:
- air
- epidermal
- fever
- bacteria
- cell phones
- cancer
- illness
- water

Fact 1: Cells that divide uncontrollably may form a tumor, or abnormal mass of cells. Fact 2: Cancer is a malignant tumor. Given the two facts above, cells that divide uncontrollably may form what?
****
A:
cancer