Which two scientists worked together to develop a tree-dimensional model of dna

Matteo makes raspberry punch. the table shows how many parts ginger ale and raspberry juice to use for a batch. raspberry punch parts ginger ale 2 parts raspberry juice 3 matteo decides to add one part of raspberry juice. what is the new ratio of ginger ale to raspberry juice?

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

Arley is building a model of a city map. in one part of the city, three roads form a right triangle, which harley draws as triangle abc, with the following measures: m∠b=90° and m∠a=30°. in his scale model, the hypotenuse of triangle abc, ac¯¯¯¯¯¯¯¯, has a length of 817−−√ cm. what is the value of a (the length of bc¯¯¯¯¯¯¯¯)?