hi, i have this code:

`F = 4000.0; % force`

m = 1300.0; % mass

A = 3.0; % frontal area, [m^2]

Cd = 0.6; % drag coefficient, [-]

rho = 1.23; %air density

v0 = 5; %velocity at t = x = 0

vTerm = sqrt(2*F/(Cd*rho*A)); %terminal velocity

dxdt = @(t,x)(sqrt((2.*F)./(Cd.*rho.*A))); % V(t) = diff( X(t) ,t )

tspan =[0 100]; %

x0 = 0;opts = odeset('RelTol',1e-8,'AbsTol',1e-8);[t,x] = ode45(dxdt, tspan, x0,opts);

first i need to set the relative tolerance to 1e-8 by using odeset before using ode45 to solve for x and t, which i'm unfamiliar with so can i get some comment on what i did whether its right or not ??, if not, any suggestion would be appreciated, thanks.

secondly, i now need to find t and x at which the velocity reach 99% of vTerm and i got no where trying to solve it. i think one of the problem could be that my function was wrong since i dont think its return the v0=5 as in the question, but i cant seem to find another function for it. Can i please have some help, thank you

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