Why can even small oil spills have a serious impact

Oil spills frequently kill marine mammals such as whales, dolphins, seals, and sea otters. ... Oil coats fur of otters and seals, leaving them vulnerable to hypothermia. Even when marine mammals escape the immediate effects, an oil spill can contaminate their food supply.

in the simplest terms possible, a small oil spill can drip into stormdrains and then it flows to rivers and bays/oceans then contaminating what water and poisoning the wildlife and plants there

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

the relative standard reduction potential of the half-cell in which reduction occurs; more positive than the other half-cell. reduction is a chemical process in which electrons are added to an atom or an ion; it always occurs accompanied by oxidation of the reducing agent.