What would be the radius r of a sphere of neptunium-237 that has a critical mass?

Select all of the quadrants that the parabola whose equation is y=√x-4 (principal square root) occupies. i ii iii iv

Identify the type of observational study described. a statistical analyst obtains data about ankle injuries by examining a hospital's records from the past 3 years. cross-sectional retrospective prospective

Will give brainliest plz hurry lexie surveyed 4 teenagers to find out approximately how many hours, per week, they read for fun, and how many siblings they have. brooke said she reads about 10 h a week for fun, and that she has 5 siblings. celia said she has 1 brother and 1 sister and reads for fun about 3 h each week. henry said he has 2 brothers and reads for fun about 30 min each week. jude said he doesn't read for fun and has 3 brothers and 3 sisters. use this information to complete the data table. express your answers as whole numbers or decimals. name hours of fun number of siblings brooke celia __ henry jude