En el otoño de 2002,un grupo de científicos de los Alamos Nacional laboratorios determinó que la masa crítica del Neptunio 237 es de unos 60kg. La materia crítica de una materia fisionable es la cantidad mínima que debe juntarse para iniciar una relación en cadena. este elemento tiene una densidad de 19.5gcm3 ¿Cuál sera el radio de una esfera de este material que que tiene dicha masa critica?

If you had $1,900,000, how many days would it take you to spend all if you spent $1 a second. (there are 86,400 seconds in a day)

Acompany manufactures large valves, packed in boxes. a shipment consists of 1500 valves packed in 75 boxes. each box has the outer dimensions 1.2 x 0.8 x 1.6 m and the inner dimensions 1.19 x 0.79 x 1.59 m. the boxes are loaded on a vehicle (truck + trailer). the available capacity in the vehicle combination is 140 m3. each valve has a volume of 0.06 m3. - calculate the load factor on the box level (%). - calculate the load factor on the vehicle level (%). - calculate the overall load factor (%).

I’m on question 7 it says a covered water tank is in the shape of a cylinder the tank has a 28 inch diameter and a height of 66 inches to the nearest square inch what is the surface area of the water tank