He has to use a different colored light at a higher frequency.
Answer:
The required volume of hexane is 0.66245 Liters.
Explanation:
Volume of octane = v=1.0 L=
Density of octane= d = 
Mass of octane ,m= 
Moles of octane =
Mole percentage of Hexane = 45%
Mole percentage of octane = 100% - 45% = 55%

Total moles = 11.212 mol
Moles of hexane :

Moles of hexane = 5.0454 mol
Mass of 5.0454 moles of hexane,M = 5.0454 mol × 86 g/mol=433.9044 g
Density of the hexane,D = 
Volume of hexane = V

(1 cm^3= 0.001 L)
The required volume of hexane is 0.66245 Liters.
Answer:
B. Chemical changes produce new substances; physical changes do not.
Explanation:
Physical changes only alter appearances, while chemical changes are interactions that create new chemical formulas.
The best title for this note will be FEATURES AND APPLICATION OF ULTRASOUND.
All the points listed above are characteristics and uses of ultrasound. Ultrasound is defined as the sound wave which has frequency that is higher than the upper audible limit of human hearing. It is used in many fields including medical field. In the medical field, ultrasound is used as a diagnostics tool to treat many disease conditions.
B) 50 J because it had less energy at the beginning than the end