Find all multiples of 9 less than 10000 whose only digits are 1 and/or 8?

Which solid has two triangular bases and three lateral faces, each in the shape of a rectangle? triangular prism triangular pyramid rectangular prism rectangular pyramid

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle

The birth weights of newborn babies in the unites states follow in a normal distrubution with a mean of 3.4 kg and standard deviation of 0.6 kg. reaserches interested in studying how. children gain weights decide to take random samples of 100 newborn babies and calculate the sample mean birth weights for each sample