It takes longer to obtain a drilling permit or to receive approval of an expanded permit to be allowed to drill a well deeper than originally permitted.
The decoder rat had the same types of levers in its chamber, but it did not receive any visual cue indicating which lever it should press to obtain a reward.
In their study, the US researchers found that animals worked harder to get doses of Nocaine than to receive a saline solution, but less hard than they did to obtain doses of cocaine.
In Brazil's favelas, it helped some 900, 000 people obtain "potable water piped directly into their homes, " and about 1 million receive sewer services.
Those agreements allow students to receive their associate's degrees if they earned enough credits toward them but didn't actually obtain them before heading to a four-year school.