Suppose a small quantity of radon gas, which has a half-life of 3.8 days, is accidentally released into the air in a laboratory. if the resulting radiation level is 40% above the safe level, how long should the laboratory remain vacated? (hint: to start with, determine what fraction of the "resulting radiation level" is the maximum safe level.) the laboratory should remain vacated for how many day?

Need now max recorded the heights of 500 male humans. he found that the heights were normally distributed around a mean of 177 centimeters. which statements about max’s data must be true? a) the median of max’s data is 250 b) more than half of the data points max recorded were 177 centimeters. c) a data point chosen at random is as likely to be above the mean as it is to be below the mean. d) every height within three standard deviations of the mean is equally likely to be chosen if a data point is selected at random.

Can some one explain this i got sent this. is this a threat i’m scared

Describe the symmetry of the figure. identify lines of symmetry, if any. find the angle and the order of any rotational symmetry.